The spectral/hp element modelling of steady flow in non‐planar double bends

The purpose of this study is to better understand steady flow in three‐dimensional non‐planar double bend geometries which are chosen to loosely model a right coronary or femoral artery, neglecting branches. The knowledge gained from idealized geometries can subsequently be applied to anatomically correct geometries. The three‐dimensional computations of steady flows in planar and non‐planar double bends at Reynolds numbers of 125 and 500 were performed using a high accuracy, spectral/ hp element Navier–Stokes solver. In this study, we analyse the haemodynamics in terms of various mechanical factors (i.e. axial velocity, secondary flows, vorticity and coherent vortical structures). Although the effects of curvature and non‐planarity on the flows are complex and often non‐intuitive, from the numerical results, we can simplify and anticipate the secondary flow patterns, and by associations the wall shear stress distribution, in various double bend geometries with different non‐planarities at physiological Reynolds number (100⩽ Re ⩽500). Non‐planarity has the biggest effects on mixing and swirling of flow as observed through the coherent vortical structures and asymmetric secondary flow streamlines.